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1.
The crystal structures of the four E,Z,E isomers of 1‐(4‐alk­oxy­phen­yl)‐6‐(4‐nitro­phen­yl)hexa‐1,3,5‐triene, namely (E,Z,E)‐1‐(4‐methoxy­phen­yl)‐6‐(4‐nitro­phen­yl)hexa‐1,3,5‐triene, C19H17NO3, (E,Z,E)‐1‐(4‐ethoxy­phen­yl)‐6‐(4‐nitro­phen­yl)hexa‐1,3,5‐triene, C20H19NO3, (E,Z,E)‐1‐(4‐nitro­phen­yl)‐6‐(4‐n‐propoxyphen­yl)hexa‐1,3,5‐triene, C21H21NO3, and (E,Z,E)‐1‐(4‐n‐butoxy­phen­yl)‐6‐(4‐nitro­phen­yl)hexa‐1,3,5‐triene, C22H23NO3, have been determined. Inter­molecular N⋯O dipole inter­actions between the nitro groups are observed for the meth­oxy derivative, while for the eth­oxy derivative, two adjacent mol­ecules are linked at both ends through N⋯O dipole–dipole inter­actions between the N atom of the nitro group and the O atom of the eth­oxy group to form a supra­molecular ring‐like structure. In the crystal structures of the n‐prop­oxy and n‐but­oxy derivatives, the shortest inter­molecular distances are those between the two O atoms of the alk­oxy groups. Thus, the nearest two mol­ecules form an S‐shaped supra­molecular dimer in these crystal structures.  相似文献   

2.
The course of the singlet‐oxygen reaction with pregn‐17(20)‐enes and pregn‐5,17(20)‐dienes was studied to compare the reactivity of the two alkene moieties present in some steroid families. Thus, from commercially available (3β,5α)‐hydroxy‐androstan‐17‐one and (3β)‐3‐hydroxyandrost‐5‐en‐17‐one, the following 3‐{[(tert‐butyl)dimethylsilyl]oxy}‐substituted, 17(20)‐unsaturated pregnanes were prepared (see Fig. 1): (3β,5α)‐21‐norpregn‐17(20)‐ene 1 ; (3β,5α,17Z)‐pregn‐17(20)‐ene 2 , (3β,5α,16α,17E)‐pregn‐17(20)‐en‐16‐ol 3 , (16β,5α,17E)‐pregn‐17(20)‐en‐16‐ol 4 , (3β,5α,16β,17E)‐pregn‐17(20)‐en‐16‐ol acetate 5 , (3β,16α)‐21‐norpregna‐5,17(20)‐dien‐16‐ol 6 , (3β,16α,17E)‐pregna‐5,17(20)‐dien‐16‐ol 7 , (3β,17Z)‐pregna‐5,17(20)‐diene 8 , (3β,17E)‐pregna‐5,17(20)‐dien‐21‐ol 9 and (3β,17E)‐5,17(20)‐dien‐21‐ol acetate 10 . The oxygenated products (see Fig. 2) obtained from 1 – 10 and 1O2, generated by irradiation of Rose Bengal in 3O2‐saturated pyridine solution, were characterized by 1H‐, 13C‐NMR, and MS (EI, FAB, HR‐EI, ESI‐ and UV‐MALDI‐TOF) data. Major products were those formed by the ene reaction involving as intermediates the corresponding hydroperoxides and the cyclic tautomers of the allylic hydroperoxides, i.e., the corresponding oxiranium oxide‐like intermediate (Scheme 5).  相似文献   

3.
Following our phytochemical studies of Costa Rican plants, we report the isolation of two new 3,4‐seco‐ent‐kaurenes from the aerial parts of Croton megistocarpus (Euphorbiaceae). The structures of the two compounds were elucidated as 14‐[(2‐methylbutanoyl)oxy]‐3,4‐seco‐ent‐kaura‐4(19),16‐dien‐3‐oic acid ( 1 ) and 14‐{[(2Z)‐2‐methylbut‐2‐enoyl]oxy}‐3,4‐seco‐ent‐kaura‐4(19),16‐dien‐3‐oic acid ( 2 ). In addition, seven known diterpene clerodanes were also isolated and identified. The structures of the compounds were elucidated by spectroscopic methods, including HR‐MS, 1H‐NMR, 13C‐NMR, COSY, HMQC, HMBC, and NOESY experiments.  相似文献   

4.
On the Mechanism of the Cope Rearrangement The rates of the Cope rearrangement of 2,5-dicyano-3-methyl-hexa-1, 5-diene ( 12 ), (E)- and (Z)-2, 5-dicyano-hepta-1,5-diene ((E)- and (Z)- 14 ) as well as of 2, 5-dimethoxycarbonyl-3-methyl-hexa-1,5-diene ( 13 ) and (E)- and (Z)-2,5-dimethoxycarbonyl-hepta-1,5-diene ((E)- and (Z)- 15 ) were measured in decane solution in the temperature range of 50 to 150° (see Tables 5 and 8 to 12). A detailed English summary of this work is given in [1 b].  相似文献   

5.
Two new tetracyclic triterpenoids shiona‐19(E),21‐dien‐3β‐ol ( 1 ), and shiona‐22(29)‐en‐3β,21‐diol ( 2 ), together with four known compounds shiona‐21‐en‐3β‐ol ( 3 ), friedelinol ( 4 ), β‐sitosterol ( 5 ), and (24R)‐stigmast‐7,22(E)‐dien‐3a‐ol ( 6 ) were isolated from Aster ageratoides var. oophyllus. The structures of two new compounds were established on the basis of IR, MS, 1H, 13C and 2D NMR spectroscopic methods.  相似文献   

6.
The sponges Raspailia pumila and ramosa (Demospongiae, Tetractinomorpha, Axinellida) from the North-East Atlantic are shown to contain a series of novel long-chain enol ethers of glycerol where the enol ether C?C bond is conjugated, in sequence, to both an acetylenic and an olefinic bond. Polar extracts give raspailynes hydroxylated at their (1Z5Z)-1,5-alkadien-3-ynyl chain, like raspailyne Al ( = (+)-(S)-3-[((1Z,5Z)-16-hydroxy-hexadeca-1,5-dien-3-ynyl)oxy]-1,2-propanediol; (+ 2 ) and isoraspailyne A ( = (+)-3-[((1Z,5Z)-17-hydroxyocta-deca-1,5-dien-3-ynyl)oxy]-1,2-[propanediol; (+)- 3 ). Less polar extracts give 3 different types of raspailynes not hydroxylated at the chain. Raspailynes of the first type have either the (1Z,5Z)-configuration in a linear chain such as raspailyne B2 (( = (?)-(s)-3-[((1Z,5Z)-trideca-1,5-dien-3-ynyl)oxy]-1,2-propanediol; (?)-4), raspailyne Bl ( = (?)-3-[((1Z,5Z)-tetradeca-1,5-dien-3-ynyl)oxy]-1,2-propanediol;(?)- 5 ), and raspailyne B ( = 3-[((1Z,5Z)-pentadeca-1,5-dien-3-ynyl)oxy]-1,2-propanediol; 6 ) or the (1Z,5Z)-pentadeca-1,5-dien-3-ynyl)oxy]-1,2-propanediol; 6 )or the (1Z,5Z)-configuration in a chain ending with an isopropyl group, like isoraspailyne Bl ( = 3-[((1Z,5Z)-12-methyltrideca-1,5-dien-3-ynyl)oxy]-1,2-propanediol; 7 ) and isoraspailyne B ( = 3-[((1Z,5Z)-13-methyltetradeca-1,5-dien-3-ynyl)oxy]-1,2-propanediol; 8 ). Raspailynes of the second type have the (1Z,5E)-configuration, like isoraspailyne Bla ( =3-[((1Z,5E)-tetradeca-1,5-dien-3-ynyl)oxy]-1,2-propanediol; 9 ) and isoraspailyne Ba ( = 3-[((1Z,5E)-13-methyltetradeca-1,5-dien-3-ynyl)oxy]-1,2-propanediol; 10 ). Raspailynes of the third type have the (1E,5Z)-configuration, like isoraspailyne Blb ( = 3-[((1E,5Z)-tetradeca-1,5-dien-3-ynyl)oxy]-1,2,-propanediol; 11 ). The (S)-configuration for (+)- 1 ,((+)- 2 , and (?)- 4 is derived from chemical correlations.  相似文献   

7.
The compound [VO(dien)]2GeS4 ( 1 , dien = diethylenetriamine) features an ortho‐thiogermanate anion [GeS4]4–, which acts as tetradentate ligand joining [VO(dien)]2– complexes. The compound was obtained under solvothermal conditions crystallizing in thenon‐centrosymmetric orthorhombic space group Pna21 with a =19.8310(11), b = 8.0814(5), c = 12.0889(9) Å, V = 1937.4(2) Å3 and Z = 4. The V4+ cations are in a distorted octahedral environment of a tridentate dien molecule, one oxygen atom and two sulfur atoms from the [GeS4]4– anion. A three‐dimensional network is generated by hydrogen bonding interactions.  相似文献   

8.
The attempted Baylis-Hillman reactions of sulfonyl aldimines or aryl aldehydes with 3-methylpenta-3,4-dien-2-one or 3-benzylpenta-3,4-dien-2-one gave the corresponding Baylis-Hillman adducts in moderate yields in DMSO under the catalysis of DBU or PMe3, respectively. Moderate diastereoselectivities were observed in the reaction of 3-benzylpenta-3,4-dien-2-one with N-arylmethylidene-1-naphthalenesulfonamides catalyzed by chiral catalyst cinchona alkaloid derivative TQO {4-(3-ethyl-4-oxa-1-azatricyclo[4.4.0.0^3,8]dec-5-yl)quinolin-6-ol}.  相似文献   

9.
Two new compounds, (6S,13S)‐6‐{[β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}cleroda‐3,14‐dien‐13‐ol ( 1 ) and kadsuric acid 3‐methyl ester ( 2 ), together with nine known compounds, (6S,13E)‐6‐{[β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}cleroda‐3,13‐dien‐15‐ol ( 3 ), (6S,13S)‐6‐[6‐O‐acetyl‐β‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}‐13‐{[α‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐fucopyranosyl]oxy}cleroda‐3,14‐diene ( 4 ), (6S,13S)‐6‐{[6‐Oβ‐D ‐glucopyranosyl‐(1→4)‐α‐L ‐rhamnopyranosyl]oxy}‐13‐{[α‐L ‐rhamnopyranosyl‐(1→4)‐β‐D ‐fucopyranosyl]oxy}cleroda‐3,14‐diene ( 5 ), 15‐hydroxydehydroabietic acid ( 6 ), 15‐hydroxylabd‐8(17)‐en‐19‐oic acid ( 7 ), junicedric acid ( 8 ), (4β)‐kaur‐16‐en‐18‐oic acid ( 9 ), (4β)‐16‐hydroxykauran‐18‐oic acid ( 10 ), and (4β,16β)‐16‐hydroxykauran‐18‐oic acid ( 11 ) were isolated from the fronds of Dicranopteris linearis or D. ampla. Their structures were established by extensive 1D‐ and 2D‐NMR spectroscopy. Compounds 1 and 3 – 8 showed no anti‐HIV activities.  相似文献   

10.
Stereoselective syntheses of 1,6‐bis(tributylstannyl)hexa‐1,3,5‐trienes, 1,8‐bis(tributylstannyl)octa‐1,3,5,7‐tetraenes, and 1,10‐bis(tributylstannyl)deca‐1,3,5,7,9‐pentaenes with various methylation patterns were achieved based on stereocomplementary C?C bond‐forming reactions. All‐E isomers resulted from Ramberg–Bäcklund rearrangements of distannylated diallyl‐, allylpentadienyl‐, or bis‐ (pentadienyl)sulfones. Mono‐Z‐configured 1,ω‐bis(tributylstannyl)‐1,3,5‐polyenes emerged from (Sylvestre–)Julia olefinations of Bu3Sn‐substituted enals or dienals with Bu3Sn‐substituted allyl or pentadienyl benzothiazolylsulfones. Related Ramberg–Bäcklund approaches provided all‐E‐1‐bromo‐6‐(tributylstannyl)hexa‐1,3,5‐triene but not all‐E‐1‐(tetramethyldioxaborolanyl)‐6‐(tributylstannyl)hexa‐1,3,5‐triene.  相似文献   

11.
A minor, unprecedented diterpene, 3β,17‐dihydroxycleistantha‐12,15‐dien‐2‐one ( 1 ), was isolated from the CHCl3‐soluble part of the EtOH extract of the pericarp of Trewia nudiflora. The structure of 1 was elucidated by means of 1D‐ and 2D‐NMR spectroscopic analyses as well as by HR‐MS. Also isolated were two known triterpenes, glutin‐5‐en‐3‐ol and olean‐18‐en‐3‐one (germanicone), as well as three known sterols, (22E,24R)‐5α,8α‐epidioxyergosta‐6,22‐dien‐3β‐ol, (22E,24R)‐5α,8α‐epidioxyergosta‐6,9(11),22‐trien‐3β‐ol, and (22E,24R)‐6‐methoxyergosta‐7,22‐dien‐3,5‐diol.  相似文献   

12.
The title compounds, 2‐{[tris­(hydroxy­methyl)­methyl]­amino­methyl­ene}cyclo­hexa‐3,5‐dien‐1(2H)‐one, C11H15NO4, (I), 6‐hydroxy‐2‐{[tris­(hydroxy­methyl)­methyl]­amino­methyl­ene}­cyclo­hexa‐3,5‐dien‐1(2H)‐one, C11H15NO5, (II), and 6‐methoxy‐2‐{[tris­(hydroxy­methyl)­methyl]­amino­methyl­ene}­cyclo­hexa‐3,5‐dien‐1(2H)‐one, C12H17NO5, (III), adopt the keto–amine tautomeric form, with the formal hydroxy H atom located on the N atom, and the NH group and oxo O atom display a strong intramolecular N—H⋯O hydrogen bond. The N—H⋯O hydrogen‐bonded rings are almost planar and coupled with the cyclo­hexa­diene rings. The carbonyl O atoms accept two other H atoms from the alcohol groups of adjacent mol­ecules in (I), and one from the alcohol and one from the phenol group in (II), but from only one alcohol H atom in (III).  相似文献   

13.
Four new eudesmane‐type sesquiterpene derivatives, 3β‐[(β‐D ‐glucopyranosyl)oxy]‐11αH‐eudesm‐4(14)‐en‐12,8β‐olide ( 1 ), (3β)‐eudesma‐4(14),11(13)‐diene‐3,12‐diol ( 2 ), 3β‐[(β‐D ‐glucopyranosyl)oxy]eudesma‐4(14),11(13)‐dien‐12‐ol ( 3 ), and 3β‐[(β‐D ‐glucopyranosyl)oxy]eudesm‐4(14)‐en‐11‐ol ( 4 ), together with the known (3β)‐eudesm‐4(14)‐ene‐3,11‐diol ( 5 ) were isolated from Saussurea conica, and their structures were elucidated both spectroscopically and by chemical methods.  相似文献   

14.
The accessibility of triads with deltahedral Zintl clusters in analogy to fullerene–linker–fullerene triads is another example for the close relationship between fullerenes and Zintl clusters. The compound {[K(2.2.2‐crypt)]4[RGe9‐CHCH CHCH‐Ge9R]}(toluene)2 (R=(2Z,4E)‐7‐amino‐5‐aza‐hepta‐2,4‐dien‐2‐yl), containing two deltahedral [Ge9] clusters linked by a conjugated (1Z,3Z)‐buta‐1,3‐dien‐1,4‐diyl bridge, was synthesized through the reaction of 1,4‐bis(trimethylsilyl)butadiyne with K4Ge9 in ethylenediamine and crystallized after the addition of 2.2.2‐cryptand and toluene. The compound was characterized by single‐crystal structure analysis as well asNMR and IR spectroscopy.  相似文献   

15.
The planar 3,4‐diphosphinidenecyclobutene (DPCB) can be remarkably twisted into a C2‐type helical structure by dual coordination of a AuCl moiety. A prompt chirality control of the twisted DPCB skeleton ligated by the digold units affords the enantiopure structure by exchanging the chloride ligands for chiral [1,1′‐binaphthalene]‐2,2′‐dicarboxylate. The chirality of the diaurated 2,2′‐bis(diphenylphosphanyl)‐1,1′‐biphenyl (BIPHEP) system can be controlled prior to that of DPCB. Mixing of a DPCB‐bis(chlorogold) complex with the chiral silver salt dynamically leads to a single diastereomer, which was characterized by the 31P NMR spectrum and the CD couplet patterns in the visible (DPCB) area. The absolute configuration of the singly induced helical structure was assigned by the theoretical CD spectra determined by TD‐DFT calculations. Intramolecular alkoxycyclization of hexa‐4,5‐dien‐1‐ol catalyzed by the asymmetric DPCB‐digold structure were also attempted.  相似文献   

16.
Treatment of cycloalkanone dimethyl acetals 3 – 6 with sorbyl alcohol (=(2E,4E)‐hexa‐2,4‐dien‐1‐ol; 1 ) in the presence of acids afforded the novel cycloalkenones 8, 9, 11 , and 13 via a domino reaction (Claisen rearrangement with intramolecular ene reaction and retro‐ene reaction). Cyclopentenone 8 was readily transformed into 14 and 15 , methyl homologues of racemic methyl jasmonate ( 16 ) and methyl dihydrojasmonate (=Hedione®; 17 ), respectively. The organoleptic properties of 14 and 15 are also discussed.  相似文献   

17.
Two novel triterpenoids, lantadienone ( 1 ) and camaradienone ( 2 ), were isolated from the aerial parts of Lantana camara, along with seven known compounds, lantadene A, lantadene B, β‐sitosterol 3‐(β‐D ‐glucopyranoside), camaric acid, lantanilic acid, lantanolic acid, and camangeloyl acid. Their structures were elucidated as (3β,22β)‐3,25‐epoxy‐3‐hydroxy‐22{[(2Z)‐2‐methyl‐1‐oxobut‐2‐enyl]oxy}‐28‐noroleana‐12,17‐dien‐11‐one ( 1 ) and (3β)‐3,25‐epoxy‐3‐hydroxy‐28‐noroleana‐12,17‐dien‐11‐one ( 2 ), respectively, by means of spectral studies. The triterpenoids 1 and 2 represent 28‐noroleananes oxidized at C(11) and C(22) or at C(11), reported for the first time.  相似文献   

18.
A kinetic study is reported for SNAr reactions of 2,4,6‐tris(trifluoromethanesulfonyl) anisole 1a with a series of para‐X‐substituted anilines 2a–e in a methanol solution at various temperatures. The substituent effects on free energy (ΔG), enthalpy (ΔH), and entropy (ΔS) of activation are examined. Aniline addition to triflone 1a is characterized by a βX=0.57, αZ=0.31, and an imbalance of I = αZ–βX=?0.26. The imbalance shows that resonance development lags behind C? N bond formation at the transition state. Interestingly, analysis of the results in terms of Marcus theory reveals that these SNAr are associated with some extremely low intrinsic reactivity (log ko=?1.25& © 2011 Wiley Peiodicals, Inc. Int J Chem Kinet 43: 255–262, 2011  相似文献   

19.
The accessibility of triads with deltahedral Zintl clusters in analogy to fullerene–linker–fullerene triads is another example for the close relationship between fullerenes and Zintl clusters. The compound {[K(2.2.2‐crypt)]4[RGe9‐CH?CH? CH?CH‐Ge9R]}(toluene)2 (R=(2Z,4E)‐7‐amino‐5‐aza‐hepta‐2,4‐dien‐2‐yl), containing two deltahedral [Ge9] clusters linked by a conjugated (1Z,3Z)‐buta‐1,3‐dien‐1,4‐diyl bridge, was synthesized through the reaction of 1,4‐bis(trimethylsilyl)butadiyne with K4Ge9 in ethylenediamine and crystallized after the addition of 2.2.2‐cryptand and toluene. The compound was characterized by single‐crystal structure analysis as well asNMR and IR spectroscopy.  相似文献   

20.
A three‐dimensional cyano‐bridged copper(II) complex, [Cu(dien)Ag(CN)2]2[Ag2(CN)3][Ag(CN)2] ( 1 ) (dien = diethylenetriamine), has been prepared and characterized by X‐ray crystallography. Complex 1 crystallized in the monoclinic space group P21/n with a = 6.988(2), b = 17.615(6), c = 12.564(4) Å, β = 90.790(5)°. The crystal consists of cis‐[Cu(dien)]2+ units bridged by [Ag(CN)2] to form a zig‐zag chain. The Ag atoms of the free and bridging [Ag(CN)2] link together to form additional infinite zig‐zag chains with short Ag···Ag distances. The presence of Ag···Ag interactions effectively increases the dimensionality from a 1‐D chain to a 3‐D coordination polymer.  相似文献   

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